Download doclava when building for Android and use to build cronet Javadocs

build/android/download_doclava.py

+#!/usr/bin/env python
+# Copyright 2016 The Chromium Authors. All rights reserved.
+# Use of this source code is governed by a BSD-style license that can be
+# found in the LICENSE file.
+
+"""Minimal tool to download doclava from Google storage when building for
+Android."""
+
+import os
+import shutil
+import subprocess
+import sys
+
+
+# Its existence signifies an Android checkout.
+ANDROID_ONLY_DIR = os.path.join(os.path.dirname(os.path.abspath(__file__)),
+                                os.pardir, os.pardir,
+                                'third_party', 'android_tools')
+
+
+def ReadFile(filename):
+  with file(filename, 'r') as f:
+    return f.read().strip()
+
+
+def WriteFile(filename, content):
+  assert not os.path.exists(filename)
+  with file(filename, 'w') as f:
+    f.write(content)
+    f.write('\n')
+
+
+def main():
+  # Some Windows bots inadvertently have third_party/android_tools installed,
+  # but are unable to run download_from_google_storage because depot_tools
+  # is not in their path, so avoid failure and bail.
+  if sys.platform == 'win32':
+    return 0
+  if not os.path.exists(ANDROID_ONLY_DIR):
+    return 0
+
+  outdir = os.path.join('src', 'buildtools', 'android', 'doclava')
+  tarball = outdir + '.tar.gz'
+  sha1file = tarball + '.sha1'
+  stampfile = tarball + '.stamp'
+
+  checksum = ReadFile(sha1file)
+
+  if os.path.exists(stampfile):
+    if (os.path.exists(tarball) and
+        os.path.exists(outdir) and
+        checksum == ReadFile(stampfile)):
+      return 0
+    else:
+      os.unlink(stampfile)
+
+  subprocess.check_call([
+      'download_from_google_storage',
+      '--no_resume',
+      '--no_auth',
+      '--bucket', 'chromium-doclava',
+      '-s', sha1file])

[agrieve, 2016/04/11 17:12:56]

You should add a comment saying why --extract doesn't work.

+  assert os.path.exists(tarball)
+
+  if os.path.exists(outdir):
+    shutil.rmtree(outdir)
+  assert not os.path.exists(outdir)
+  os.makedirs(outdir)
+  assert os.path.exists(outdir)
+
+  print "Extracting", tarball
+  subprocess.check_call(['tar', 'axf', os.path.abspath(tarball)], cwd=outdir)

[agrieve, 2016/04/11 17:12:57]

Probably better to use Python's tarfile module for this rather than
sub-shelling. (Should be just a couple of lines)

+
+  WriteFile(stampfile, checksum)
+  return 0
+
+if __name__ == '__main__':
+  sys.exit(main())